It is estimated that 1 in 5 Americans suffer from allergic rhinitis/conjunctivitis (AR). AR is the result of an IgE mediated immune system response to inhaled aero-allergens, which typically include dust mite, fungi, animal dander, pollutants, molds, and pollens. For those individuals afflicted by AR, the short term effects extend beyond the physical symptoms found in the eyes and nose, often resulting in cognitive impairment, sleep disturbance, lowered work/school productivity, and reductions in quality of life. More alarmingly, if AR symptoms persist on a long term basis the disease can lead to the development of comorbities, including asthma, sinusitis, otitis media, nasal polyposis, lower respiratory tract infection, and dental malocclusion.
Typical treatment for AR consists of three steps. First, the trigger allergen(s) is identified and environmental control measures are employed to minimize allergen exposure. Second, if elimination steps are unsuccessful, medication is employed to manage and control symptoms. Third, for perennial allergen exposure, immunotherapy may be undertaken to obtain long term symptom control. Allergen avoidance is the preferred treatment, providing symptom resolution absent medication. But to date few allergen avoidance measures exist that reduce airborne allergen concentrations to a clinically relevant level.
Effective allergen avoidance focuses on two basic principles: identification of the offending allergen source, and removal/elimination of the offending source or reduction of the concentration of inhaled aero-allergens. Commonly practiced allergen avoidance measures that are clinically effective include pet removal from the home and geographic re-location. Other forms of allergen avoidance that are of questionable clinical effectiveness but are commonly practiced include whole room air filtration, dust mite casings, use of air conditioning, and carpet removal.
Of the listed allergen avoidance measures, air filtration systems, some of which remove particulates at 99.97% efficiency, show great promise for reducing inhaled aero-allergen concentrations to a clinically relevant level. However, the current practice of such technologies limit their effectiveness. For example, people often utilize room air cleaner units in an attempt to achieve a reduction in particle levels within a localized area. These types of units effectively remove a high percentage of harmful particles from the air that flows through the unit. However, individuals within the area of the unit may not experience all of the beneficial results of this particle removal because the air that is discharged from the unit is able to pick up additional harmful particles from the surrounding environment prior to reaching and being breathed in by the individuals. Furthermore, the effectiveness of air cleaners and purifiers is greatly affected by the size of the room, such that results worsen as the room size increases. Other room factors such as air-tightness, the presence of air currents and traffic which can kick up particles, also affect the performance of air cleaners and purifiers. In the case of dust mites residing in bedding, a room air filter can not adequately reduce the allergenic exposure between the bedding and the person sleeping in the bed. Given these factors, it is difficult for an air cleaner or purifier to significantly reduce the levels of allergens and pollutants being breathed by an individual.
Prior art air cleaners have attempted to reduce these problems by directing air directly into the face of a sleeping person. Such devices must blow a considerable wind on to the sleeping person's head in order to prevent ambient particles from circulating near the person while sleeping. Such high wind levels may be annoying to a person who is trying to sleep. Furthermore, many of these devices are cumbersome, expensive and unsightly.